Radio frequency plasma comprehensive testing device and method for ion process system

Abstract

The present invention discloses a radio frequency plasma comprehensive testing device and method for an ion process system, and relates to the field of plasma testing technology. The device comprises a host and a coupling probe; the coupling probe is placed on the radio frequency transmission line of the ion process system, and is used to couple and sample radio frequency energy through capacitance or induction coupling according to the electromagnetic field coupling principle, obtain current and voltage signals through coupling, and is also used to sense and obtain real-time temperature data inside the probe; the host comprises a main body shell and a shielding frame arranged in the main body shell, and a data processing and analysis unit is provided inside the shielding frame, which is used to process the received voltage, current and temperature signals, calculate and generate radio frequency power supply power, radio frequency power supply spectrum, impedance of a matcher and a vacuum reaction chamber, and other ion process system parameter values, and at the same time output clutter capture in radio frequency transmission and radio frequency transmission harmonic test results, thereby realizing comprehensive testing of the ion process system.

Description

Technical Field

[0001] The present invention relates to the field of plasma testing technology, and in particular to a radio frequency plasma comprehensive testing device and method for an ion process system. Background Art

[0002] The statements in this section merely provide background information related to the present invention and do not necessarily constitute prior art.

[0003] Plasma-related processes are currently one of the most important processes in the semiconductor field. Plasma-related applications require an ion process system. The entire ion process system includes an RF power supply to generate the RF energy required for ions, RF coaxial cables and RF connectors to transmit the RF energy, an RF power supply matcher to adjust the overall transmission impedance, and a vacuum reaction chamber that provides the necessary environment for plasma generation. The main problems faced in ion process systems are the instability of the RF power supply and the overall impedance matching of the ion process system. Among them: An RF power supply is essentially a high-power device that amplifies small RF signals into large signals. Due to its operating principle, noise and harmonics are inevitable. Once noise and harmonics appear, they will affect the instability of the process and thus the yield of the chip. As a high-intensity, long-term used device, the RF power supply often faces the problem of component aging. Once the problem of component aging occurs, the output of the RF power supply will be offset, thereby affecting the accuracy of each process. Impedance changes are also one of the important factors affecting the RF power supply. Parameters such as power, voltage, and current phase in the ion process system must be closely matched to preset parameters to demonstrate the reliability of the semiconductor process cycle and ensure process stability (i.e., guaranteeing yield and efficiency). Therefore, whether it is an ion process system undergoing initial commissioning or an ion process system that has been put into production and has been operating for a long time, the reliability of the ion process system must be frequently tested. Only by ensuring consistent power, voltage, and current and voltage phases in the ion process can the chip manufacturing process be fundamentally guaranteed.

[0004] To test the reliability of ion process systems, a variety of testing methods have been proposed, including:

[0005] (1) The through-type power meter test solution, as the most common test solution in the industry, usually consists of several power sensors, RF components, power meters, and high-power dummy loads. Its main function is to accurately measure the power value of the RF power supply and judge the status of the overall line connection based on this power value. However, the test instruments required for this method are extremely expensive, with high subsequent maintenance costs and limited functions. They can only test the power value, but cannot capture clutter and harmonics, nor can they measure impedance.

[0006] (2) Absorption power meter testing solution, as a more common testing solution in the industry, usually consists of a power attenuator and an absorption power meter. Its main function is to test the output power of the RF power supply. This method is a relatively low-cost testing solution, but it cannot monitor the actual working power status of the RF power supply when connected to the machine, nor can it determine the connection status of the entire line. It has a single function and can only test the power value. It cannot capture clutter and harmonics, nor can it measure impedance.

[0007] (3) Spectrum analyzer test solution, as a more common test solution in the industry, usually consists of a high-power coupler and a spectrum analyzer. This solution can test the spectrum of the RF power supply, and by analyzing the spectrum, it can test the noise and harmonics of the RF power supply, and test the stability of the RF power supply in the frequency dimension. However, this solution has a single function and cannot test the power value of the RF power supply.

[0008] (4) The VI sensor test solution, a relatively rare test solution in the industry, usually consists of a VI probe and an adapted host analysis module. It can analyze the voltage and current information in the transmission line through calculation to obtain the impedance parameter. It can also calculate power based on the voltage and current information. However, the equipment used in this solution is expensive, the cost is high, and the power is obtained by calculation, which has low accuracy, poor overall ease of use, and high technical requirements for users.

[0009] Therefore, existing testing solutions for ion process systems have certain limitations, and most can only address or solve one aspect of the problem, achieving a single test function. While comprehensive testing using all of the aforementioned equipment can address these limitations to a certain extent, it is prohibitively expensive and requires constant disassembly and assembly to obtain the required multiple values, making the operation unnecessarily cumbersome and complex. Summary of the Invention

[0010] To address the deficiencies of the above-mentioned prior art, the present invention provides a radio frequency plasma comprehensive testing device and method for ion process systems. According to the principle of electromagnetic field coupling, an induction probe is designed to couple and sample the radio frequency energy transmitted in the radio frequency cable, and then the coupled current, voltage, temperature and other signals are analyzed and processed. In this way, the power detection of the radio frequency power supply, the spectrum analysis of the radio frequency power supply, the impedance analysis of the matcher and the vacuum reaction chamber, the capture of clutter in radio frequency transmission, the harmonic testing in radio frequency transmission, the capture of arcs in the plasma vacuum reaction chamber, the capture of possible radio frequency leakage in the transmission line, and the testing of various parameters of the ion process system (such as standing wave ratio, insertion loss, return loss, impedance, etc.) are simultaneously completed, thereby achieving the simultaneous completion of multiple functions and avoiding the high cost and limitations of existing testing devices.

[0011] In a first aspect, the present invention provides a radio frequency plasma comprehensive testing device for an ion process system.

[0012] A radio frequency plasma comprehensive testing device for ion process systems, comprising a host and a coupling probe;

[0013] The coupling probe is placed on the RF transmission line of the ion process system and is used to couple and sample RF energy through capacitive or inductive coupling based on the principle of electromagnetic field coupling, obtain current and voltage signals through coupling, and to sense and obtain real-time temperature data inside the probe;

[0014] The host includes a main shell and a shielding frame arranged inside the main shell. A data processing and analysis unit is provided inside the shielding frame. The data processing and analysis unit is used to process the received voltage, current and temperature signals, calculate and generate RF power supply power, RF power supply spectrum, impedance of the matcher and vacuum reaction chamber and other ion process system parameter values, and output the results of clutter capture and RF transmission harmonic test in RF transmission.

[0015] In a further technical solution, the coupling probe is integrated with a central sensing conductor, a temperature acquisition unit, a current acquisition unit, a voltage acquisition unit and a signal transmission unit; wherein:

[0016] The central inductive conductor is used to couple and sample radio frequency energy through capacitive or inductive coupling according to the electromagnetic field coupling principle;

[0017] The current acquisition unit and the voltage acquisition unit are both electrically connected to the central sensing conductor and are used to obtain the current and voltage original signals according to the coupling sampling results of the central sensing conductor;

[0018] The temperature acquisition unit is a temperature sensor built into the coupling probe, which is used to collect temperature data inside the probe in real time;

[0019] The signal transmission unit is electrically connected to the host through voltage and current signal transmission lines and temperature signal transmission lines, and is used to transmit the collected voltage, current, and temperature signals to the data processing and analysis unit of the host.

[0020] A further technical solution is that a power supply unit and a mainboard control unit are further provided inside the shielding frame, a display panel and an operation panel are embedded in the main housing, and the power supply unit, the data processing and analysis unit, the display panel, and the operation panel are all electrically connected to the mainboard control unit, wherein:

[0021] The power supply unit is used to supply power to the entire device;

[0022] The operation panel is provided with a variety of buttons for generating control signals according to human operation and transmitting the control signals to the mainboard control unit;

[0023] The display panel uses an LED, LCD or OLED touch screen to display the controllable interface and the content sent by the display mainboard control unit;

[0024] The mainboard control unit is used to integrate and drive other units to operate.

[0025] A further technical solution is that the device is also provided with an expansion unit, which includes an expansion data acquisition unit arranged inside the host and an expansion sensor unit connected to the expansion data acquisition unit. The expansion sensor unit adopts any one or more sensors of a dual directional coupling probe and an antenna receiving module.

[0026] According to a further technical solution, an antenna receiving module is provided in the expansion sensor unit, and the antenna receiving module is used to collect signals and record the radio frequency signal strength received at different positions and time points;

[0027] The extended data acquisition unit is used to receive the acquisition signal and transmit the received signal to the data processing and analysis unit;

[0028] The data processing and analysis unit is used to analyze the spectrum of the signal and identify possible radio frequency leakage in the transmission line.

[0029] In a second aspect, the present invention provides a radio frequency plasma comprehensive testing method for an ion process system.

[0030] A radio frequency plasma comprehensive testing method for an ion process system is implemented based on the radio frequency plasma comprehensive testing device for an ion process system proposed in the first aspect, the method comprising:

[0031] Place the coupling probe of the radio frequency plasma comprehensive test device on the radio frequency transmission line of the ion process system, and start the radio frequency plasma comprehensive test device;

[0032] Using a coupling probe, based on the principle of electromagnetic field coupling, the radio frequency energy is sampled through capacitive or inductive coupling, and current and voltage signals are obtained through coupling. At the same time, real-time temperature data inside the probe is obtained by sensing, and the obtained current, voltage and temperature data are transmitted to the host.

[0033] Based on the data processing and analysis unit inside the host, the received voltage, current and temperature signals are processed to calculate and generate the RF power supply power, RF power supply spectrum, impedance of the matcher and vacuum reaction chamber and other ion process system parameter values, and at the same time output the clutter capture in RF transmission and RF transmission harmonic test results.

[0034] Further technical solutions also include:

[0035] Using the expansion unit in the radio frequency plasma comprehensive test device, an antenna receiving module is added to the expansion sensor unit of the expansion unit;

[0036] Use the antenna receiving module to collect signals and record the RF signal strength received at different locations and time points;

[0037] Based on the received collected signal, the signal spectrum is analyzed to identify possible RF leakage in the transmission line.

[0038] One or more of the above technical solutions have the following beneficial effects:

[0039] The present invention provides a radio frequency plasma comprehensive testing device and method for an ion process system. According to the electromagnetic field coupling principle, an induction probe is designed to couple and sample the radio frequency energy transmitted in the radio frequency cable, and then the coupled current, voltage, temperature and other signals are analyzed and processed. In this way, the power detection of the radio frequency power supply, the spectrum analysis of the radio frequency power supply, the impedance analysis of the matcher and the vacuum reaction chamber, the capture of clutter in radio frequency transmission, the harmonic testing work in radio frequency transmission, the capture of arcs in the plasma vacuum reaction chamber, the capture of possible radio frequency leakage in the transmission line, and the testing of various parameters of the ion process system (such as standing wave ratio, insertion loss, return loss, impedance, etc.) are simultaneously completed, thereby achieving the simultaneous completion of multiple functions and avoiding the high cost and limitations of existing testing devices.

[0040] The comprehensive test device proposed in the present invention is based on fixed or customized probes and is applied to ion process systems composed of semiconductor RF power supplies, energy transmission systems, RF power supply matchers, and plasma vacuum reaction chambers. It can realize online measurement of the forward and reverse power, voltage, current, phase value, and impedance of RF power supply signals. At the same time, it supports signal capture of up to five fundamental frequencies and up to four harmonics, arc detection in vacuum reaction chambers, and analysis of RF waveforms in the time domain during the process. In addition, by adding expansion units and expansion sensors, a certain degree of expansion can be carried out on the basis of the above basic functions, such as matching network efficiency testing, RF power supply fault analysis, and detection of RF leakage in the test environment, which makes the application more comprehensive and wider.

[0041] Advantages of additional aspects of the present invention will be given in part in the following description and in part will be obvious from the following description, or will be learned through practice of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0042] The accompanying drawings, which constitute a part of the present invention, are used to provide a further understanding of the present invention. The exemplary embodiments of the present invention and their descriptions are used to explain the present invention and do not constitute improper limitations on the present invention.

[0043] Figure 1 This is a schematic structural diagram of the radio frequency plasma comprehensive testing device according to an embodiment of the present invention;

[0044] Figure 2 Schematic diagram of the structure of the coupling probe in the device according to an embodiment of the present invention;

[0045] Figure 3 A schematic diagram of testing using a coupling probe according to an embodiment of the present invention;

[0046] Figure 4 Schematic diagram of the test environment when performing temperature calibration in an embodiment of the present invention;

[0047] Figure 5 Schematic diagram of the structure of the host in the device according to an embodiment of the present invention. DETAILED DESCRIPTION

[0048] It should be noted that the following detailed descriptions are exemplary only and are intended to describe specific embodiments and provide further explanation of the present invention, and are not intended to limit the exemplary embodiments according to the present invention. Unless otherwise indicated, all technical and scientific terms used herein have the same meanings as those commonly understood by those of ordinary skill in the art to which the present invention belongs. In addition, it should be understood that when the terms "comprise" and / or "include" are used in this specification, they indicate the presence of features, steps, operations, devices, components and / or combinations thereof.

[0049] Example 1

[0050] This embodiment provides a radio frequency plasma comprehensive testing device for ion process systems, such as Figure 1 As shown, the device mainly includes a host part and a coupling probe part (also called a sensor part).

[0051] like Figure 3 As shown, the ion process system using an RF power supply to generate plasma includes an RF power supply for generating the RF energy required for ions, an RF cable for transmitting the RF energy, an RF power supply matcher for adjusting the overall transmission impedance, and a vacuum reaction chamber that provides the necessary environment for plasma generation. The RF energy generated by the RF power supply enters the chamber through the cable, where the upper and lower plates inside the chamber dissociate the gas into plasma. A coupling probe (referred to as the probe) is placed on the RF transmission line of the ion process system and is used to sample the RF energy through capacitive or inductive coupling based on the principle of electromagnetic field coupling. The coupled probe obtains current and voltage signals through coupling and is also used to sense and obtain real-time temperature data inside the probe.

[0052] For the coupling probe proposed in this embodiment, Figure 2 As shown, the probe integrates a central sensing conductor, a temperature acquisition unit, a current acquisition unit, a voltage acquisition unit and a signal transmission unit. The central sensing conductor is made of good conductor materials such as copper, aluminum, silver, and gold. According to the principle of electromagnetic field coupling, capacitive coupling or inductive coupling is selected to couple and sample the radio frequency energy. The current acquisition unit and the voltage acquisition unit are both electrically connected to the central sensing conductor, and they obtain the original current and voltage signals respectively through coupling. That is, these two units are used to obtain the original current and voltage signals based on the coupling sampling results of the central sensing conductor.

[0053] The electromagnetic field coupling principle refers to the mutual conversion between magnetic and electric fields based on Maxwell's equations. When the current or voltage in a circuit or component changes, a changing electromagnetic field is generated in the surrounding space. This changing electromagnetic field interacts with other nearby circuits or components, inducing current or voltage in these circuits or components, achieving coupled energy or signal transfer. This embodiment, based on the electromagnetic field coupling principle, uses capacitive or inductive coupling to obtain current and voltage signals through coupling.

[0054] As an implementation method, capacitive coupling can transmit the changing electromagnetic field between two opposing conductors without contact, while isolating DC. The materials used (such as ceramic capacitors, film capacitors, mica capacitors, etc.) have the characteristics of low equivalent resistance and low dielectric loss. For this reason, this embodiment adopts capacitive coupling. Based on the characteristics of capacitance and the advantages of PCB, PCB type capacitors are designed and manufactured. They have the characteristics of small size, easy integration, compliance with environmental protection standards, controllable and stable capacitance, higher voltage resistance and temperature stability. Preferably, the dielectric material in capacitive coupling can be adaptively selected according to the specific application environment.

[0055] As another implementation, inductive coupling is based on Faraday's law of electromagnetic induction, which states that a changing magnetic field generates an induced electromotive force in a conductor, thereby achieving magnetic field-to-current conversion and, in turn, coupling. Inductive coupling can be implemented using transformers, magnetic rings, magnetic ring coils, and other methods. This embodiment uses a PCB coil to create equivalent inductance. Compared to the bulky size of traditional coil coupling, the inductive coupling method employed in this embodiment offers strong integration, customizability, low loss, low distortion, and low EMI. This ensures a smaller probe size and facilitates integration into the probe.

[0056] Furthermore, considering that probes are typically used in high-power environments with high ambient temperatures, temperature changes in the probe will cause changes in the response of internal circuit components. Therefore, it is necessary to control the temperature drift of the entire instrument or device, otherwise the accuracy of the final coupled induction signal will be affected. To this end, this embodiment also includes a built-in temperature acquisition unit, namely a built-in temperature sensor, in the coupled probe. This temperature sensor collects internal probe temperature data for temperature calibration, adjusts data signal deviations caused by temperature drift, and thus improves accuracy.

[0057] After obtaining the current, voltage, and temperature data, all data are aggregated and transmitted to the signal transmission unit in the coupling probe of this embodiment, such as Figure 1 As shown, the signal transmission unit is electrically connected to the main body part of the comprehensive test device through voltage, current signal transmission lines and temperature signal transmission lines to transmit data. The signal transmission unit transmits the three types of collected signals to the data processing and analysis unit of the main body.

[0058] like Figure 5As shown, the host part of the comprehensive test device (also known as the comprehensive test platform) proposed in this embodiment includes a main shell and a shielding frame, wherein the shielding frame is arranged inside the main shell, and the main shell is made of plastic material to make the device lighter, and the shielding frame is made of sheet metal technology, and its material can be stainless steel, aluminum alloy, copper and other materials with stable structure and good conductivity. The shielding frame serves as a support for the internal PCB and can screen external electromagnetic interference to ensure the accuracy of internal data processing and analysis.

[0059] The shielding frame is also provided with a power supply unit, a data processing and analysis unit, and a mainboard control unit. The main shell is embedded with a display panel and an operation panel to facilitate the use of the device. The power supply unit, data processing and analysis unit, display panel, and operation panel are all electrically connected to the mainboard control unit. The power supply unit is used to power the entire device, that is, to supply power to all units or modules requiring power, such as the display panel. The operation panel is equipped with buttons such as quick jump to the main software functions, numeric key input, and control buttons, which are used to generate control signals based on human operation and transmit these control signals to the mainboard control unit. The display panel uses a touch screen such as LED, LCD, or OLED to display the controllable interface and the content issued by the mainboard control unit. The mainboard control unit is equipped with an operating system and independently developed comprehensive tester supporting software. It also undertakes some calculation and analysis functions, used to integrate and drive other units, and realize functional expansion based on the data processing and analysis unit, such as spectrum analysis and Smith chart functions. The data processing and analysis unit is used to process the received voltage, current, and temperature signals, calculate and generate RF power supply power, RF power supply spectrum, impedance of the matching device and vacuum reaction chamber, and other ion process system parameters, and output the results of RF transmission interference capture and RF transmission harmonic test.

[0060] Specifically, the data processing and analysis unit performs data processing based on the three acquired signal data of voltage, current, and temperature. The voltage signal is subjected to detection processing to convert the AC signal into a DC signal, which is then input into a high-speed analog-to-digital converter (ADC) for calculating the values ​​of parameters such as the RF power supply power. The current signal is subjected to digital orthogonal mixing processing to calculate the values ​​of parameters such as the impedance of the matching device and the vacuum reaction chamber. The temperature signal is sensed by the temperature sensor built into the coupling probe. This signal is a DC signal, which is directly input into the high-speed analog-to-digital converter (ADC) for temperature-based data calibration. The specific process of the above data processing and analysis includes:

[0061] (1) First, the amplitude and phase of the voltage and current signals obtained by coupling are calculated and adjusted.

[0062] Specifically, considering that the voltage and current signals obtained through electromagnetic field coupling will change in amplitude and phase compared to the original signals, for example, the voltage signal will be affected by the original signal frequency, capacitance value, and PCB material, and the current signal is related to factors such as the PCB coil inductance, Q value (quality factor), and PCB material, therefore, in this embodiment, the voltage and current signals obtained by coupling are first calculated and adjusted to obtain data that is closer to the original signal to ensure the accuracy of subsequent test results.

[0063] (1.1) Signal amplitude adjustment.

[0064] First, for the voltage and current signals obtained through electromagnetic field coupling, the high-speed analog-to-digital converter ADC is used to collect the signals, and then the initial amplitude of the signals is analyzed by combining the signal buffer unit FPGA and the data analysis unit DSP. Specifically, suppose the collected signal is ,in is the initial amplitude.

[0065] Secondly, determine the target amplitude: that is, use a precision voltage sensor to determine the target amplitude to be adjusted .

[0066] Next, choose an adjustment method: use a programmable amplifier or attenuator to adjust the amplitude. If a programmable amplifier is used, the amplifier gain G must be determined; if an attenuator is used, the attenuation coefficient k must be determined. The signal amplitude is calculated as:

[0067] For the case of using an amplifier: If an amplifier is used to increase the signal amplitude, the calculation formula of the gain G is: Gain . With the initial amplitude And the target amplitude For example, G=5.

[0068] For the case of using an attenuator: If an attenuator is used to reduce the signal amplitude, the calculation formula for the attenuation coefficient k is: and . With the initial amplitude And the target amplitude For example, the attenuation coefficient is .

[0069] Then, make adjustments: input the collected signal into the amplifier or attenuator to obtain the adjusted signal. .

[0070] Finally, repeat the above steps to calibrate the voltage values ​​of the full voltage range at certain intervals and store the calibration data in the encrypted Flash.

[0071] Furthermore, the current amplitude is determined by the calibrated voltage and impedance.

[0072] (1.2) Signal phase adjustment.

[0073] First, measure the phase: that is, use a phase measuring instrument (such as an oscilloscope or spectrum analyzer) to measure the original phase of the collected signal , and use the DSP data analysis unit to calculate the phase of the coupled signal ;

[0074] Secondly, adjust the phase: that is, adjust the phase of the signal at the software level through the digital signal processing algorithm according to the original phase obtained by measurement and the phase of the coupled signal. In this embodiment, an analog phase shifter (whose phase shift amount is ), the discrete signal is subjected to phase rotation operation to achieve phase adjustment. For example, where T is the sampling period, if the phase is adjusted to , can be calculated by To get the adjusted signal, the sum angle formula of trigonometric function can be used After expanding it, it is calculated and processed according to the characteristics of the discrete signal.

[0075] (2) Secondly, the adjusted voltage and current signals are temperature corrected according to the temperature data obtained in real time.

[0076] In this embodiment, a temperature sensor is built into the coupling probe to capture the temperature inside the probe in real time and transmit the temperature back to the host computer comprehensive tester (i.e., the comprehensive test device proposed in this embodiment) through a separate signal line. During calibration, the following is constructed: Figure 4 The test environment shown is used for temperature calibration. Specifically, the output power of the standard source is set, the temperature of the temperature control box is controlled, and coupled signal data is collected under temperature offset conditions. Based on the collected voltage and current signal data at different temperatures, data analysis software (such as Matlab) is used to perform data fitting. The fitted temperature offset curve and its curve formula are then derived, forming a temperature calibration algorithm.

[0077] During the specific implementation process, the adjusted voltage and current signals are temperature corrected based on the pre-acquired temperature offset curve and the real-time temperature data to obtain more accurate data that is closer to the original signal, thereby ensuring the accuracy of subsequent test results.

[0078] (3) Finally, based on the corrected voltage and current signals, the power of the RF power supply, the spectrum of the RF power supply, the impedance of the matcher and the vacuum reaction chamber, and other parameter values ​​of the ion process system are calculated simultaneously, such as the capture of clutter in RF transmission, the harmonic test in RF transmission, the arc capture in the plasma vacuum reaction chamber, and the standing wave ratio, insertion loss, return loss, impedance parameters and other data in the ion process system, so as to achieve the simultaneous completion of multiple functions and avoid the high cost and limitations of existing test equipment.

[0079] Specifically, considering that existing power testing methods generally implement power measurement through attenuation and spectrum analyzer amplitude analysis, thermal resistance method, spectrum analysis method, etc., but they cannot achieve simultaneous consideration of multiple parameters such as power, voltage, current, impedance, and phase, this embodiment adopts a special coupling method to synchronously couple voltage and current signals, and calibrate other parameter data of the system from the voltage and current themselves, including:

[0080] (3.1) RF power detection: RF power detection is achieved by analyzing the effective value of the forward and reverse coupled signals and calculating the forward and reverse power using the fixed coupling degree of the probe.

[0081] Specifically, the detection power is: ;

[0082] Among them, U and I are the effective values ​​of voltage and current respectively. The voltage and current signals change according to the sinusoidal law, and their instantaneous value expressions are: ,in and are the maximum values ​​of voltage and current respectively, w is the angular frequency, and is the initial phase, then is the phase difference between voltage and current; is the power factor.

[0083] (3.2) RF Power Spectrum. Spectral analysis is performed based on the voltage and current signals obtained through coupling. Specifically, the voltage and current digital signals output by the high-speed ADC are filtered using a digital FIR (Finite Impulse Response) filter or an IIR (Infinite-Duration Impulse Response) filter. Fast Fourier Transform (FFT) or Discrete Fourier Transform (DFT) is then performed to obtain the corresponding signal spectrum. Using a high sampling rate, the frequency points are displayed on the display panel in a "time-frequency" relationship, showing the frequency points and their changing trends over a period of time.

[0084] (3.3) Impedance Analysis of the Matching Module and Vacuum Reactor. Based on the collected voltage and current values, low frequencies are extracted through digital orthogonal mixing. The sampling rate is then reduced through decimation. The resulting spectrum is then low-pass filtered to generate a shaping function. This is used to calculate the overall impedance of the matching module and vacuum reactor.

[0085] (3.4) Clutter capture in RF transmission: Clutter can be filtered out through the spectrum analysis in (3.2) above.

[0086] (3.5) RF transmission harmonic test. Similarly, harmonics are usually integer multiples of the fundamental frequency and can be screened out through the spectrum analysis mentioned above (3.2).

[0087] (3.6) Ion process system parameter testing, including: standing wave ratio, insertion loss, return loss, impedance, etc. Combined with the impedance value obtained in (3.3) above, the standing wave ratio, insertion loss, and return loss can be calculated respectively.

[0088] Among them, the standing wave ratio is the ratio of the maximum value to the minimum value of the standing wave on the transmission line, which is used to measure the impedance matching degree of the transmission line. Specifically, the characteristic impedance of the transmission line is (Usually the characteristic impedance ), the load impedance is (The load impedance is the actual measured impedance value, that is, the impedance value of the vacuum reaction chamber and the matching device), the calculation formula of the standing wave ratio is:

[0089] ;

[0090] in, is the reflection coefficient, .

[0091] Insertion loss refers to the signal power loss caused by inserting a component or device into the transmission system, usually expressed in decibels (dB). and the characteristic impedance of the transmission line , the calculation formula for insertion loss is: .

[0092] Return loss refers to the decibel ratio of the reflected wave power to the incident wave power, which reflects the degree of reflection caused by impedance mismatch during signal transmission. , the return loss calculation formula is: .

[0093] (3.7) Arc Capture in a Plasma Vacuum Reactor Chamber. When an arc occurs in a vacuum reactor, the impedance of the entire transmission line changes momentarily. As long as the sampling rate is high enough, the arc can be captured. Analyzing the frequency of arc occurrence helps analyze the stability of the overall process.

[0094] Arc capture is a phenomenon in semiconductor processing where an arc occurs due to an overly strong electric field, which causes electrical breakdown in gases and the formation of a plasma. This allows current to flow through a normally insulating medium (such as air). This arc manifests as an abnormal voltage, so detection is performed at a high-frequency sampling rate in the MHz range. If the voltage drops and then rises again within a very short period of time (approximately a few microseconds), an arc is detected.

[0095] As another implementation, the device proposed in this embodiment is further provided with an expansion unit, such as Figure 1 As shown, the expansion unit, as an additional signal processing part, can provide a data processing takeover function. In this embodiment, the expansion unit includes an expansion data acquisition unit arranged inside the host, and an expansion sensor unit connected to the expansion data acquisition unit. The expansion sensor unit can adopt a dual-directional coupling probe, an antenna receiving module, etc. By setting up the expansion unit, more functional expansions can be provided for the test platform. Its main function is to open more sensor connection ports. According to the actual needs of customers, it can support a variety of different types of sensors. For example, if one or more identical sensors need to be added, the expansion unit only needs to add the corresponding number of probes to simultaneously detect two or more signals; if a dual-directional coupling probe is added, the expansion unit can also test the reverse signal; if a receiving end antenna is added, the radio frequency leakage in the environment can be tested.

[0096] In this embodiment, an antenna receiving module is provided in the sensor unit to further capture possible radio frequency leakage in the transmission line. Specifically, the process of capturing radio frequency leakage is as follows:

[0097] First, prepare the equipment: a biconical antenna or a dipole antenna, and the comprehensive tester proposed in this embodiment.

[0098] Next, set up the test environment. Place the receiving antenna in the environment where RF leakage needs to be tested, such as near devices that may cause RF leakage or at different distances to fully assess the RF leakage situation. Also, ensure that the antenna's installation position and orientation are not subject to interference from other objects. Minimize the risk of metal objects and electromagnetic shielding materials that may affect the antenna's received signal.

[0099] Next, collect the signal. Turn on the device and set parameters such as center frequency, scan bandwidth, and resolution bandwidth. The center frequency should be set to the frequency or frequency band of the target RF signal. The scan bandwidth needs to be wide enough to cover the frequency range of possible leakage signals. The resolution bandwidth affects the accuracy of signal measurement. After setting these parameters, use the antenna receiving module to collect signals (using either continuous scanning or fixed-point measurement), recording the received RF signal strength at different locations and time points.

[0100] The collected signal is then transmitted to the extended data acquisition unit, which receives the signal and transmits it to the data processing and analysis unit. The data processing and analysis unit then performs spectrum analysis on the signal, identifies signal characteristics that may indicate RF leakage (such as path loss and power density), analyzes signal strength, frequency distribution, time domain characteristics, etc., and determines the severity and possible source of the RF leakage.

[0101] The path loss of the signal during propagation is calculated to evaluate the signal intensity attenuation at different distances. The calculation formula for the path loss is:

[0102] ;

[0103] Where L is the path loss in dB, f is the signal frequency in MHz, and d is the propagation distance in km.

[0104] In addition, the power density is calculated to measure the RF power received per unit area. The calculation formula for the power density is:

[0105] ;

[0106] Where S is the power density, the unit is W / ; P is the transmission power, unit is W; r is the distance from the transmission source, unit is m.

[0107] Finally, the results are evaluated and reported. Based on the measurement and analysis results, the system assesses whether the RF leakage in the environment exceeds the limits of relevant standards or regulations. If so, further measures are determined, such as improving the device's shielding performance, adjusting the device's location or operating parameters, etc.

[0108] The comprehensive test device proposed in this embodiment is applied to an ion process system consisting of a semiconductor RF power supply, an energy transmission system, an RF power supply matcher, and a plasma vacuum reaction chamber based on fixed or customized probes. This allows for online measurement of the forward and reverse power, voltage, current, phase, and impedance of the RF power supply signal. It also supports signal capture of up to five fundamental frequencies and up to the fourth harmonic, arc detection in the vacuum reaction chamber, and analysis of RF waveforms in the time domain during the process. Furthermore, through the aforementioned expansion units and expansion sensors, the aforementioned basic functions can be expanded to a certain extent, such as matching network efficiency testing, RF power supply fault analysis, and detection of RF leakage in the test environment.

[0109] Example 2

[0110] This embodiment provides a radio frequency plasma comprehensive testing method for an ion process system, which is implemented based on a radio frequency plasma comprehensive testing device for an ion process system proposed in Example 1. The method includes:

[0111] Place the coupling probe of the radio frequency plasma comprehensive test device on the radio frequency transmission line of the ion process system, and start the radio frequency plasma comprehensive test device;

[0112] Using a coupling probe, based on the principle of electromagnetic field coupling, the radio frequency energy is sampled through capacitive or inductive coupling, and current and voltage signals are obtained through coupling. At the same time, real-time temperature data inside the probe is obtained by sensing, and the obtained current, voltage and temperature data are transmitted to the host.

[0113] Based on the data processing and analysis unit inside the host, the received voltage, current and temperature signals are processed to calculate and generate the RF power supply power, RF power supply spectrum, impedance of the matcher and vacuum reaction chamber and other ion process system parameter values, and at the same time output the clutter capture in RF transmission and RF transmission harmonic test results.

[0114] The above-mentioned radio frequency plasma comprehensive testing method further includes:

[0115] Using the expansion unit in the radio frequency plasma comprehensive test device, an antenna receiving module is added to the expansion sensor unit of the expansion unit;

[0116] Use the antenna receiving module to collect signals and record the RF signal strength received at different locations and time points;

[0117] Based on the received collected signal, the signal spectrum is analyzed to identify possible RF leakage in the transmission line.

[0118] Furthermore, the data processing of the received voltage, current and temperature signals includes:

[0119] Calculate and adjust the amplitude and phase of the voltage and current signals obtained by coupling;

[0120] Perform temperature correction on the adjusted voltage and current signals based on the real-time acquired temperature data;

[0121] Based on the corrected voltage and current signals, the power of the RF power supply, the spectrum of the RF power supply, the impedance of the matcher and vacuum reaction chamber, the capture of clutter in RF transmission, the harmonic test in RF transmission, the arc capture in the plasma vacuum reaction chamber, and the standing wave ratio, insertion loss, return loss, and impedance parameter data in the ion process system are calculated simultaneously.

[0122] The steps involved in the above embodiment 2 correspond to those in embodiment 1. For the specific implementation method, please refer to the relevant description part of embodiment 1.

[0123] Those skilled in the art will appreciate that the modules or steps of the present invention described above can be implemented using a general-purpose computer device. Alternatively, they can be implemented using program code executable by a computing device, which can then be stored in a storage device and executed by the computing device. Alternatively, they can be fabricated into separate integrated circuit modules, or multiple modules or steps can be fabricated into a single integrated circuit module for implementation. The present invention is not limited to any specific combination of hardware and software.

[0124] The above description is only a preferred embodiment of the present invention. Although the specific implementation of the present invention is described in conjunction with the accompanying drawings, it does not limit the scope of protection of the present invention. Those skilled in the art should understand that on the basis of the technical solution of the present invention, various modifications or variations that can be made by those skilled in the art without creative work are still within the scope of protection of the present invention.

Claims

1. A radio frequency plasma comprehensive testing device for ion process systems, characterized in that: Including host and coupling probe; The coupling probe is placed on the RF transmission line of the ion process system and is used to couple and sample RF energy through capacitive or inductive coupling based on the principle of electromagnetic field coupling, obtain current and voltage signals through coupling, and to sense and obtain real-time temperature data inside the probe; The host includes a main body shell and a shielding frame arranged in the main body shell. A data processing and analysis unit is provided inside the shielding frame. The data processing and analysis unit is used to process the received voltage, current and temperature signals, calculate and generate RF power supply power, RF power supply spectrum, impedance of the matching device and the vacuum reaction chamber, arc capture in the plasma vacuum reaction chamber, and standing wave ratio, insertion loss, return loss, and impedance parameter data in the ion process system, and output clutter capture in RF transmission and RF transmission harmonic test results. The coupling probe is integrated with a central sensing conductor, a temperature acquisition unit, a current acquisition unit, a voltage acquisition unit and a signal transmission unit; wherein: The central inductive conductor is used to couple and sample radio frequency energy through capacitive or inductive coupling according to the electromagnetic field coupling principle; The current acquisition unit and the voltage acquisition unit are both electrically connected to the central sensing conductor and are used to obtain the current and voltage original signals according to the coupling sampling results of the central sensing conductor; The temperature acquisition unit is a temperature sensor built into the coupling probe, which is used to collect temperature data inside the probe in real time; The signal transmission unit is electrically connected to the host through voltage and current signal transmission lines and temperature signal transmission lines, and is used to transmit the collected voltage, current and temperature signals to the data processing and analysis unit of the host; The data processing of the received voltage, current and temperature signals includes: Calculate and adjust the amplitude and phase of the voltage and current signals obtained by coupling; Perform temperature correction on the adjusted voltage and current signals based on the real-time acquired temperature data; Based on the corrected voltage and current signals, the power of the RF power supply, the spectrum of the RF power supply, the impedance of the matcher and vacuum reaction chamber, the capture of clutter in RF transmission, the harmonic test in RF transmission, the arc capture in the plasma vacuum reaction chamber, and the standing wave ratio, insertion loss, return loss, and impedance parameter data in the ion process system are calculated simultaneously.

2. The radio frequency plasma comprehensive testing device for ion process systems according to claim 1, characterized in that: The shielding frame is further provided with a power supply unit and a mainboard control unit. The main housing is embedded with a display panel and an operation panel. The power supply unit, the data processing and analysis unit, the display panel, and the operation panel are all electrically connected to the mainboard control unit. The power supply unit is used to supply power to the entire device; The operation panel is provided with a variety of buttons for generating control signals according to human operation and transmitting the control signals to the mainboard control unit; The display panel uses an LED, LCD or OLED touch screen to display the controllable interface and the content sent by the display mainboard control unit; The mainboard control unit is used to integrate and drive other units to operate.

3. The radio frequency plasma comprehensive testing device for ion process systems according to claim 1, characterized in that: The temperature correction is: Pre-set the output power of the standard source, adjust the temperature of the temperature control box and collect the data deviation of the coupled voltage and current signals under temperature deviation conditions; Based on the collected voltage and current signals at different temperatures, data fitting is performed to obtain a temperature offset curve and a curve formula; According to the pre-acquired temperature offset curve and curve formula, combined with the real-time acquired temperature data, the adjusted voltage and current signals are temperature corrected to obtain corrected voltage and current signals.

4. The radio frequency plasma comprehensive testing device for ion process systems according to claim 1, characterized in that: The device is also provided with an expansion unit, which includes an expansion data acquisition unit arranged inside the host and an expansion sensor unit connected to the expansion data acquisition unit. The expansion sensor unit adopts any one or more sensors of a dual directional coupling probe and an antenna receiving module.

5. The radio frequency plasma comprehensive testing device for ion process systems according to claim 4, characterized in that: The extended sensor unit is provided with an antenna receiving module, which is used to collect signals and record the radio frequency signal strength received at different positions and time points; The extended data acquisition unit is used to receive the acquisition signal and transmit the received signal to the data processing and analysis unit; The data processing and analysis unit is used to analyze the spectrum of the signal and identify possible radio frequency leakage in the transmission line.

6. A radio frequency plasma comprehensive testing method for ion process systems, characterized in that: The method is implemented based on a radio frequency plasma comprehensive testing device for an ion process system according to any one of claims 1 to 5, comprising: Place the coupling probe of the radio frequency plasma comprehensive test device on the radio frequency transmission line of the ion process system, and start the radio frequency plasma comprehensive test device; Using a coupling probe, based on the principle of electromagnetic field coupling, the radio frequency energy is sampled through capacitive or inductive coupling, and current and voltage signals are obtained through coupling. At the same time, real-time temperature data inside the probe is obtained by sensing, and the obtained current, voltage and temperature data are transmitted to the host. Based on the data processing and analysis unit inside the host, the received voltage, current and temperature signals are processed to calculate and generate the RF power supply power, RF power supply spectrum, impedance of the matcher and vacuum reaction chamber and other ion process system parameter values, and at the same time output the clutter capture in RF transmission and RF transmission harmonic test results.

7. The radio frequency plasma comprehensive testing method for an ion process system according to claim 6, characterized in that: The data processing of the received voltage, current and temperature signals includes: Calculate and adjust the amplitude and phase of the voltage and current signals obtained by coupling; Perform temperature correction on the adjusted voltage and current signals based on the real-time acquired temperature data; Based on the corrected voltage and current signals, the power of the RF power supply, the spectrum of the RF power supply, the impedance of the matcher and vacuum reaction chamber, the capture of clutter in RF transmission, the harmonic test in RF transmission, the arc capture in the plasma vacuum reaction chamber, and the standing wave ratio, insertion loss, return loss, and impedance parameter data in the ion process system are calculated simultaneously.

8. The radio frequency plasma comprehensive testing method for ion process systems according to claim 6, characterized in that: Also includes: Using the expansion unit in the radio frequency plasma comprehensive test device, an antenna receiving module is added to the expansion sensor unit of the expansion unit; Use the antenna receiving module to collect signals and record the RF signal strength received at different locations and time points; Based on the received collected signal, the signal spectrum is analyzed to identify possible RF leakage in the transmission line.

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